Cairo, Egypt (CNN) — There is a strong likelihood that embattled Egyptian President Hosni Mubarak will step down Thursday night, CIA Director Leon Panetta told a U.S. Congressional panel.

Mubarak has agreed to yield power to his vice president, a senior U.S. official told CNN, citing contacts within the Egyptian government.

This official, speaking on condition of anonymity because of the sensitivity of the information, said that given the mixed signals sent throughout the crisis that “we need to see it happen.”

But the source said the information came from reliable and ranking officials in the Mubarak regime. Asked when the transfer of power might take place, the official said: “We are told soon is the plan.”

The secretary-general of Egypt’s ruling party confirmed Thursday that a transition was underway and he expected Mubarak to address the nation soon.

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Hosni Mubarak: In his words Hossam Badrawi, a prominent doctor who was appointed to the ruling party’s post last Saturday, told CNN he believed Mubarak’s words would “accommodate the protesters.”

Badrawi indicated that the transition process had been accelerated but he was unclear exactly when Mubarak might step down. He said certain constitutional reforms have to be implemented before the president can relinquish power.

“The process is ongoing,” Badrawi said. “This will give confidence to the protesters.”

The comments came as pressure intensified on Mubarak’s regime.

The mass demonstrations, despite stern government warnings of military intervention, remained relentless Thursday and thousands of workers in vital industries walked off their jobs in a show of solidarity with demonstrators demanding change.

The military remained out in force and many believe Egypt’s future hinges on the role it will play. Senior military officers were meeting Thursday to discuss “what can be achieved to preserve the homeland.”

Earlier in the day, protesting lawyers toppled barricades at Cairo’s Abdeen Palace, the former home of Egypt’s monarchy and a symbol of power. Armed police, who had disappeared from the streets of Cairo as the uprising gained momentum, waited behind metal fences.

But the police fled and the crowd surged amid the roar of thunder on a rainy day. “God is great,” they chanted.

Unable to enter the palace — which was under heavy army protection — the group of lawyers headed to Tahrir Square, where on the 17th day of the revolt, massive crowds again gathered to call for the immediate departure of Mubarak.

The demonstrations were galvanized earlier in the week by the words and tears of freed cyberactivist Wael Ghonim, who emerged as the face — albeit reluctant — of Egypt’s uprising.

Ghonim, on leave from his marketing job with the search engine Google in Dubai, was seized by security forces and held for 10 days before being released.

Credited with starting a Facebook page that triggered the protests, Ghonim said on Twitter Thursday: “I promise every Egyptian that I will go back to my normal life & not be involved in any politics once Egyptians fulfill their dreams.”

Hours later, he tweeted: “Mission accomplished. Thanks to all the brave young Egyptians” amid signs of possible imminent change in Egypt. Ghonim has been hailed by many fellow protesters as a hero.

Oil workers demanded transparency in executive salaries, said Hamdi Abdel-Aziz, a spokesman for the petroleum ministry.

National Railway Council employees called for longer contracts, prompting a pledge to extend them from their leaders. Some did not return to work Thursday, said Mostafa Qinawi, head of the Railway Council.

Employees of the steel industry and the Suez Canal Port Authority also took to the streets to demand better salaries, said the state-run al-Ahram newspaper. That sparked fears that the Suez Canal — a significant oil transport hub and major revenue source for Egypt — would shut down and send oil prices skyrocketing.

Egypt’s finance minister said the nation will “do its utmost best” to ensure the canal remains open.

“All precautions are taken to prevent any sabotage from outside to the Suez Canal,” Samir Hadwan told CNN. “The Suez Canal is safe and the Egyptian Army — I don’t talk on their behalf — but I can assure you it will do whatever is in its power to keep that open.”

In the Mediterranean city of Alexandria, Egypt’s second largest, street cleaners and administrative staff went on strike over what they say is a salary freeze. At least 1,000 engineers protested contracts and financial compensations, officials said.

Thursday’s demonstrations unfolded with vigor despite escalating fears of a government crackdown. Key government officials have sought to portray an immediate departure for Mubarak as a recipe for absolute mayhem and warned of military intervention.

That could lead to a “dangerous” situation, Egyptian Foreign Minister Ahmed Aboul Gheit said in two interviews Wednesday with PBS’ “Newshour” and Al-Arabiya television.

“Do we want the armed forces to assume the responsibility of stabilizing the nation through imposing martial law and the army in the streets?” Aboul Gheit said on PBS. “For the army to rule, to step in, to put its friends on the scene, that would be a very dangerous possibility.”

He said the president will not relinquish power immediately because his interest is to protect the stability of the nation.

“He thinks that it would entail chaos and it would entail violence and it would entail also opportunities for those who would wish to act in a manner to threaten the state, the stability of the country and society,” Aboul Gheit said.

Human Rights Watch has been deeply critical of the government’s handling of the crisis.

“Instead of running scared, the regime is fighting back with both words and violence to quash its opponents, portraying the opposition as a foreign-backed, un-Egyptian group of conspirators,” the monitoring group said in a statement Wednesday.

The group has documented 302 deaths since the January 25 rally that ignited Egypt’s revolt.

Prime Minister Ahmed Shafiq said on state television Thursday that he has formed a fact-finding committee to investigate events since the demonstrations began. The five-member panel has the authority to call on witnesses, Shafiq said.

The unrest on Wednesday extended beyond Cairo. Four people were killed in clashes with police in southern Egypt, state TV reported, leading to the firing of a police chief in Kharga.